Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.1.7 (acetylcholinesterase)
28,390 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mivacurium is a short-acting nondepolarising muscle relaxant of the benzylisoquinoline type undergoing rapid breakdown by plasma cholinesterase. With 2.5 fold ED95, tracheal intubation can be accomplished within 2-3 min following injection. The ensuing DUR 25% (i.e. time from injection to 25% recovery of control twitch tension) is three times as long as with succinylcholine and about half as long as with equipotent doses of atracurium and vecuronium. The principal side effects of mivacurium are facial flushing and a transient fall in blood pressure due to a moderate histamine release following doses of 3-4 times the ED95. In patients with end stage liver or renal disease as well as in patients with atypical plasma cholinesterase the duration of action of mivacurium is prolonged. Rocuronium is a steroidal non-depolarising neuromuscular blocking agent chemically related to vecuronium. Compared with the latter, rocuronium is less potent, has a shorter onset of action, and no cumulative effects. Adequate intubating conditions are achieved within 60 to 90 s after i.v. injection of twice the ED95. Its elimination from the blood occurs primarily via liver uptake, while renal elimination is about 10 to 30%. Slight vagolytic effects are reported following injection of 0.6 mg/kg rocuronium, while histamine release is unlikely to occur. Atracurium is a mixture of ten stereoisomers. One of them, cis-atracurium, is five times as potent as the chiral mixture while having a similar pharmacodynamic and kinetic profile. It does not cause significant histamine release or clinically relevant cardiovascular effects at doses up to 8 times the ED95. Laudanosine release seems to be less with cis-atracurium than with atracurium.
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PMID:[New muscle relaxants]. 886 25

Neostigmine antagonism after suxamethonium followed by mivacurium chloride bolus and infusion was studied. Thirty ASA group I or II patients were given mivacurium 0.15 mg/kg followed by infusion during nitrous oxide-enflurane-pethidine anaesthesia. Train of four (TOF) stimuli were applied to the ulnar nerve at the wrist and TOF twitch height and ratio measured by TOF-GUARD nerve stimulator. Mivacurium infusion was titrated to give a 90% block of first twitch height. Patients were randomized into two groups. Group I patients recovered from the mivacurium block spontaneously while Group II patients were given neostigmine 0.05 mg/kg and atropine 0.02 mg/kg. Time to reach train of four ratio (TOFR) of 25%, 50% and 70% were measured. This study demonstrated a mean infusion rate of 5.1 +/- 1.8 micrograms/kg/min to maintain a 90% neuromuscular block. In the spontaneous recovery group, time to reach TOFR of 25%, 50% and 70% were 9.3 +/- 2.7 min, 13.5 +/- 3.0 min and 16.7 +/- 3.0 min respectively while the corresponding times in the neostigmine group were 5.2 +/- 1.7 min, 10.9 +/- 2.2 min and 16.1 +/- 7.4 min respectively. There were significant differences in the time taken to TOFR of 25% (P < 0.0001) and 50% (P < 0.05) but no difference in the time taken for TOFR to return to 70%. We concluded that mivacurium is suitable for use in caesarean section despite a decrease in plasma cholinesterase activity. Neostigmine antagonism is not required as a routine.
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PMID:Recovery from mivacurium block with or without anticholinesterase following continuous infusion in obstetric patients. 890 71

Mivacurium is the only available short-acting nondepolarizing muscle relaxant in clinical use. It is a bis-quaternary benzylisoquinolinium ester hydrolysed by plasma-cholinesterase into inactive compounds. The ED50 and ED95 in children are about 50 micrograms.kg-1 and 90 micrograms.kg-1 respectively. In infants, they have a tendency to be lower. A standard intubating dose of 0.25 mg.kg-1 causes complete neuromuscular depression in 1.5-2 min, recovery to 5% in 6-10 min, and complete recovery in 15-20 min. The recent tendency is to use 0.3 mg.kg-1 to obtain better intubating conditions with slight prolongation of effect. Since the recovery profile of mivacurium is independent of the dose and duration, it is most suitable for administration by continuous infusion. The infusion requirement in children is 10-16 micrograms.kg-1 min-1, which is about twice that of adults. Cutaneous flushes from histamine release are commonly seen with the larger doses of mivacurium; however, the associated hypotensive effects are minimal and counteracted by the tracheal intubation. The duration of action of mivacurium is prolonged in patients with cholinesterase deficiency. Mivacurium's neuromuscular effects can be satisfactorily antagonized by edrophonium or neostigmine.
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PMID:Mivacurium in infants and children. 918 62

Mivacurium is a short-acting, nondepolarising muscle relaxant of the benzylisoquinoline type that undergoes rapid breakdown by plasma cholinesterase. After 2.5 times the ED95 (0.2 mg/kg), tracheal intubation can be accomplished within 2-3 min following injection. The ensuing DUR 25% (i.e., time from injection to 25% recovery of control twitch tension) is three times as long as with succinylcholine. The principal side effects of mivacurium are facial flushing and a transient fall in blood pressure due to moderate histamine release following doses 3-4 times the ED95. In patients with end-stage liver or renal disease as well as those with atypical plasma cholinesterase, the duration of action of mivacurium is prolonged.
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PMID:[The clinical pharmacology of mivacurium]. 924 7

Mivacurium is a short-acting nondepolarizing muscle relaxant (NDPMR) with a benzyl-isoquinoline structure and rapid, spontaneous reversal. It is hydrolyzed by cholinesterase in plasma and its chemical structure favors histamine release, leading to cutaneous or cardiovascular symptoms, particularly when the dose is increased or when the drug is injected rapidly. Both duration of effect and reversal of mivacurium are less dose dependent than they are with intermediate-duration NDPMRs. In adults the recommended dose for intubation (2 to 3 times the ED95) induces clinically effective blockade lasting 15 to 25 minutes, with spontaneous recovery occurring 10 to 20 minutes later. In children two to 12 years old given the same dose, duration of action is shorter and reversal occurs more rapidly. These properties reduce the likelihood of antagonizing the residual neuromuscular blockade. The duration of successive doses is similar and continuous infusion does not affect reversal. Neuromuscular blockade may be prolonged in patients with low plasma cholinesterase activity, particularly in individuals who are homozygous for the atypical plasma cholinesterase gene. Monitoring is therefore recommended when mivacurium is used. Provided patients have normal plasma cholinesterase activity, mivacurium is indicated for interventions that are short or of unpredictable duration when rapid reversal of neuromuscular blockade is required, or whenever anticholinesterase agents must be avoided.
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PMID:[Mivacurium]. 964 62

Anaesthetic agents for day-case surgery ideally should have a short duration of action. This study was designed to compare the efficacy and safety of mivacurium and vecuronium for healthy adults undergoing dental day-case surgery. Thirty fit healthy adult patients (ASA I or II) randomly received either mivacurium 0.15 mg kg-1 (n = 15) or vecuronium 0.1 mg kg-1 (n = 15). Anaesthesia included propofol, fentanyl, nitrous oxide and isoflurane. Maximum depression of T1 was greater in the vecuronium group (99.8%) than in the mivacurium group (98.3%). There was no difference between grade of intubation at 2 min between the two groups, although patients receiving vecuronium had a more profound block at the time of intubation than those who received mivacurium (89.2% vs. 78.9%). Recovery to 10% T1 was faster in the mivacurium group (11.2 min vs. 33.1 min). All patients in the vecuronium group received neostigmine at the termination of surgery. The neostigmine evoked recovery index in the vecuronium group (4.39 min) was less than the spontaneous recovery index in the mivacurium group (6.78 min). One patient in the mivacurium group had a low plasma cholinesterase concentration (0.43 ku L-1); recovery times however, fell within the 95% confidence intervals (CI) for the group. There was no correlation between cholinesterase levels and recovery time. Mivacurium may be the more appropriate agent for dental day-case surgery because it has a shorter duration of action and does not generally require antagonism with an anticholinesterase.
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PMID:Mivacurium or vecuronium for muscular relaxation in day-case surgery. 946

Mivacurium is a short acting non-depolarising neuromuscular blocking agent. Short duration of action is due to a rapid hydrolysis by plasma cholinesterase (CHe). The duration of neuromuscular blockade can be prolonged by an abnormal variant of CHe. We report a case of a newborn with neuromuscular blockade for a duration of 8 hours following mivacurium 0.2 mg.kg-1. CHe activity values were not contributive for the diagnosis. The diagnosis was obtained with molecular study showing the new-born homozygocity. The whole family was heterozygous. This case emphasises the lack of precision of CHe activity measurement during the first 6 months of life.
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PMID:[Prolonged neuromuscular blockade with mivacurium in a newborn]. 975 Aug 10

The pharmacokinetics of 6 new neuromuscular blocking drugs are described. These are the aminosteroids pipecuronium bromide, rocuronium bromide and rapacuronium bromide (ORG-9487) and the benzylisoquinolinium diesters doxacurium chloride, mivacurium chloride and cisatracurium besilate. In healthy individuals, these drugs all have similar volumes of distribution. Their pharmacokinetics are influenced little by age or anaesthetic technique, but renal and hepatic disease may significantly alter their distribution and elimination. Pipecuronium resembles pancuronium in its pharmacokinetic and neuromuscular blocking profile, but is devoid of cardiovascular effects. It has a low clearance (0.16 L/h/kg) and long elimination half-life (120 minutes). It is largely eliminated through the kidney. Rocuronium has a similar pharmacokinetic profile to vecuronium but its onset of action is more rapid and duration of action slightly shorter. Its clearance (0.27 L/h/kg) is intermediate between those of pipecuronium and rapacuronium, but its elimination half-life is long (83 minutes). The pharmacokinetics of rocuronium are altered by renal and hepatic disease; the latter probably has the more significant effect. Rapacuronium has a rapid onset, and a bolus dose has a short duration of action. It has a high clearance (0.59 L/h/kg) but a long elimination half-life (112 minutes). Doxacurium has a pharmacokinetic and pharmacodynamic profile similar to pipecuronium. It has a high potency and is devoid of cardiovascular effects. In adults, it has a low clearance (0.15 L/h/kg) and long elimination half-life (87 minutes). Mivacurium is a mixture of 3 stereoisomers. It has a short to intermediate duration of action. It is hydrolysed by plasma cholinesterase. Inherited or acquired alterations in plasma cholinesterase activity are associated with changes in the pharmacokinetics and time course of action of mivacurium. The 2 active isomers (cis-trans and trans-trans) have a high clearance (4.74 L/h/kg) and very short elimination half-lives (approximately 2 minutes). Cisatracurium is the 1R-cis 1'R-cis isomer of atracurium. It has similar pharmacokinetics and pharmacodynamics to atracurium. It is mainly broken down by Hofmann (non-enzymatic) degradation. Cisatracurium has an intermediate clearance (0.3 L/h/kg) and short elimination half-life (26 minutes). Hepatic and renal disease have little effect on its pharmacokinetics.
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PMID:Clinical pharmacokinetics of the newer neuromuscular blocking drugs. 1022 67

Mivacurium is metabolized by plasma cholinesterase (PCHE). Metoclopramide inhibits PCHE in vitro and in vivo. We have assessed the effect of metoclopramide on duration of action of mivacurium and measured PCHE at baseline and at the time of maximal block. In a randomized, double-blind study, 30 patients received metoclopramide 0.15 mg kg-1 i.v. or saline, followed by propofol anaesthesia and mivacurium 0.15 mg kg-1. Using a TOF-Guard accelerometer, times to recovery of TI to 25%, 75% and 90% were 13.4, 19.3 and 21.9 min in the saline group and 17.8, 25.3 and 28.8 min in the metoclopramide group (P < 0.01, P < 0.05, P < 0.05, respectively). There were no differences in onset time or recovery index between the groups. PCHE activity at the time of maximum block decreased within each group (P < 0.01) but there was no difference between groups. In a second biochemical study of eight patients, a small decrease in PCHE activity was detected after metoclopramide 0.15 mg kg-1, but before administration of mivacurium (P < 0.025). We conclude that metoclopramide prolongs the duration of action of mivacurium.
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PMID:Influence of metoclopramide on plasma cholinesterase and duration of action of mivacurium. 1047 19

Mivacurium is mainly metabolized by plasma cholinesterase, whereas atracurium is removed by Hofman elimination. The purpose of this study was to compare the infusion rate of atracurium and mivacurium in maintaining surgical relaxation, and to compare their recovery indices between parturients and non-pregnant women. Muscle relaxation was maintained by the continuous infusion of relaxants to retain the first response of train-of-four (TOF) at 5% of control. When mivacurium was used, Bolus-T5 (duration from the end of mivacurium bolus injection to 5% single twitch recovery) was measured. After discontinuing the infusion, the recovery index was measured. The infusion rate of mivacurium, not atracurium, was significantly lower in parturients and Bolus-T5 of parturients was significantly longer than that of non-pregnant women. There was no significant difference in the recovery indices of both relaxants. The authors concluded that the infusion rate of mivacurium in maintaining muscle relaxation in parturients should be reduced compared to the rate in non-pregnant women and measuring Bolus-T5 may be helpful in determining the infusion rate to maintain muscle relaxation.
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PMID:The infusion rate of mivacurium or atracurium for cesarean section compared with gynecological procedures. 1048 41


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